The present invention relates generally to a system for supporting peripheral computer cards and other optional external devices in a personal computer (PC) system More particularly, the present invention relates to a system which monitors the presence of peripheral computer cards in a PC system. Still more particularly, the present invention relates to a specially modified slot which detects whether peripheral computer cards have been installed.
The components provided in a PC system typically may comprise a combination of fixed, internal devices, and peripheral external devices that may be added to the PC system to increase the computing power or to add features not included as part of the fixed PC system supplied by the manufacturer. The PC system typically includes a motherboard on which most of the fixed internal circuitry of the PC is mounted. The circuitry typically is fabricated as discrete integrated circuits (IC's) mounted to conductive pads on the motherboard. The various IC's are connected together electrically by various electrical buses, such as for, example, a host bus, which connects the central processing unit to the memory controller and other critical components. As one skilled in the art will understand, the system bus can comprise any suitable bus system, such as an ISA, EISA, MCA, PCI or other suitable system bus.
The motherboard also typically includes sockets or external connections for receiving peripheral cards or components to supplement the circuitry provided on the motherboard. As shown in the computer 5 of FIG. 1, a riser board 10 may connect to the motherboard 15. The motherboard 15 typically is positioned horizontally in the computer case 20. The riser board 10 extends vertically from the motherboard 15, and includes expansion slots 11, 12, 13, 14. As one skilled in the art will understand, additional or fewer expansion slots may be provided by the computer manufacturer, as desired. The expansion slots are displaced vertically on the riser card 10, enabling computer cards to be inserted horizontally into the slots. In FIG. 1, an expansion card or board 25 is shown inserted into slot 12.
As one skilled in the art will understand, it is necessary to remove a portion of the computer casing 20 to access the expansion slots 11, 12, 13, 14, and to install computer cards. After the card 25 is installed, the casing cover is closed. Typically, a screwdriver is required to remove and close the casing cover of the computer. Consequently, it is not possible to confirm visually that a card 25 is installed in an expansion slot unless a portion of the casing cover 20 is removed from the computer 5, which normally requires tools, and may also require that the computer be repositioned and/or disconnected from peripheral equipment to obtain access to the removable casing cover.
Presently, conventional computer systems determine if a card is present in an expansion slot electrically, by driving signals through the electrical connectors 8 in the slot to connectors 9 on the computer card. If the card responds by transmitting signals back through the electrical connectors 8 and 9 to appropriate circuitry on the mother board, then the presence of the card is conferred. A problem arises, however, if the computer card is malfunctioning, and does not respond to signals from the computer. In that event, the only way to detect the presence of the card in the expansion slot is to visually inspect the slot by removing the computer casing cover. Similarly, if no card is present in the expansion slot (as may happen, for example, if the user confuses the slot in which the card was installed), then this fact may only be confirmed by removing the casing cover.
It would be advantageous if an expansion slot was designed with a system for mechanically detecting whether a computer card was installed in a particular slot so that the presence of the card could be confirmed even if the card was malfunctioning Despite the benefit of such a design, no such design is available commercially.